ITU Specification and Description Language as supported by tools in 2012 is mainly SDL-92 (with the 1996 addendum) with a few features of SDL-2000. SDL-2000 has now been replaced by SDL-2010, which omits some SDL-2000 features not fully supported by tools (but also adds some new features). Telecommunications Software Engineering has provided courses for this language. The 3-day course outlined below is one that has been given several times. There is also alternative prepared material the more fully cover SDL-2000 as defined by ITU-T. Work needs to be done to bring the SDL-2000 up to date with SDL-2010, but the course is normally adapted to suit client requirements in any case.


Day 1

Day 2

Day 3

Start here

Objectives of course
Overview of the language

Examples of use


Blocks in Blocks
Procedures, Services
Synonyms, Macros & Generics

Exercise 5

Other features

Other Inputs
More on Procedures
1996 features

Team Exercise(cont.)

Basic Features

Simple Processes
Basic Data

Exercise 1

Focus on Data

Predefined Data
Declarations and variables
Syntypes, Newtypes, ADTs
Checks and Errors
Operators: Imperative, Definitions
Remote, Alternative data

Exercise 6

Methodology I

Using the language

Inputs & Output

Signal data, paths, lists
Valid signal set
Queues and delays

Exercises 2, 3

SDL-92 Types

Types and Instances
Reuse of Types
Redefinition of types
Multiple Blocks

Exercise 7

Methodology II

ASN.1 and MSC

ITU-T guidelines

Formalisation Steps

Use of Documents

Review of exercise

Process Creation

Numbers: start/max.
Process Identity
self, sender, parent, offspring

Exercise 4

Team Exercise

(Exercise 8)

The objective is to tackle a specification as a team using the concepts of the language. The task needs to be small to fit time/resources.


ITU-T work
Topics not covered


Courses are arranged and tailored to meet your requirements.

Course Tutor:

Rick Reed the founder of TSE, is a world acknowledged expert in the area of formal description techniques with more than 30 years experience in software in the telecommunications industry. He has been the Rapporteur responsible for the Specification and Description Language work for ITU-T since 1992, and was previously (1992-1996) Rapporteur for language Methodology and Editor of the ITU Specification and Description Language Newsletter. He has made major contributions to international standards and has delivered successful courses on the Specification and Description Language in the UK, Europe, USA and South America.

Course content

The course was developed particularly NOT to require the use of a Specification and Description Language tool. The reasons for this were to meet the requirements of clients buying ITU Specification and Description Language tools that:

The approach adopted is therefore to use 'pencil and paper' for exercises. Tools could also be used, but the course is not intended to be a training course in the use of tools.

The price includes all documentation (including examples and example solutions). Each delegate receives full classroom notes.

The actual price will depend on the course customization and the location. For six participants at an on-site course if little or no alteration to existing material is required a typical price might be:

which includes delivery of the course, preparation of course notes, documentation etc.; subject to exactly how much customisation is required and payment terms. Additional delegates will be at a cost of 600 Euros or US Dollars per person (500 pounds sterling in the UK). The suggested maximum of for a course is sixteen.

Subject to availability, a minimum notice of 20 working days (normally=4 weeks) and a deposit of 15% with order is usually required. If the course is cancelled by the client before the course takes place, some or all of the deposit may not be returnable. The time and charge is to allow for ordering materials and other preparations.

All prices exclude VAT or any other national taxes applicable.

Last updated 22-Mar-2013

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